Device for shoring or supporting the roofs of mines



i atented Mar. 29, 1932 UNITED STATES ROBERT WILLIAM CUTHBERTSON, OF ASHFIELD, RAINHILL, ENGLAND DEVICE FOR SHORING OR SUPPORTING THE ROOFS OF MINES Application filed April 9, 1928, Serial No. 268,534, and in Great Britain May .12, 1927.

This invention relates to improvements in reinforcing girders for shoring or supporting the roof in coal or other mines of the type-1n which the reinforced girder is supported at The invention will be described with reference to the accompanying drawings Fig. 1 is a side view of areinforcing girder constructed according to the invention.

Fig. 2 is an end view thereof showing the block for anchoring the two ends of the rope.

Fig. 3 is an end view thereof showing the grooved block at the other end of the girder.

Fig. 4 is a plan view of the girder from underneath.

Fig. 5 is a perspective view, of grooved block.

The T-iron girder A is reinforced by a single wire rope B which passes along both sides of the flange a. A block-D is fixed to one end of the girder and this block is provided with an external groove (Z around which the rope B passes. A block 0 is affixed at the other end of the girder with two tapering holes 0 to receive the ends of the rope B which are held therein.

The rope B is held at each end in the block C in the two tapering holes 0, the smallest diameter of which is approximately equal to the diameter of the rope B. Each end of the rope B is inserted into a hole 0 and is spread or opened out and the hole is then filled with a suitable alloy or metal (such as white metal) in a molten state so that when the alloy or metal cools the ends of the rope are firmly secured in the block.

A roof supporting girder constructedin accordance with this invention has many advantages over other steel girders as it is of less size than an ordinary steel joist or timber bar of the same strength and moreover gives greater space in the roadway.

What I claim as my invention and desire to protect by Letters Patent is A reinforced girder for supporting the roof in coal mines and. other underground workings comprislng the combination witha T iron of a single reinforcing wire rope extending longitudinally along both sides of the web of the girder, a. grooved block afiixed at one end of the girder around which the wire rope passes and a block at the other end of the girder having two tapering transverse holes to receivethe end of the reinforcing 

